There are several critical components of an overhead crane, but the wire rope is probably at the top of the list. Should the rope break due to wear or corrosion, a load can be lost, resulting in serious damage and possibly injury or death to workers. That is why paying close attention to the wire rope in your care is critical to preventing a possible catastrophe. Cleaning and lubricating wire rope will reduce wear and halt corrosion, and below is a step-by-step guide to this important procedure:
Tools and materials needed
Compressed air blow gun
Degreasing agent in spray bottle
Penetrating lubricant and sprayer
Cleaning and lubricating—a step-by-step procedure
1. Position the bridge and wire drum—Begin by moving the bridge of the crane to a safe location where you can easily access the wire rope without interference from other machinery. In addition, be sure the location you choose for cleaning is isolated from areas where moisture sensitivity is problematic. Finally, you will want to have adequate lighting so that rust or other problems are easily visible during the cleaning process.
2. Unspool the wire rope—Once you have chosen a good location for cleaning and lubrication, lower the hoist to the ground and be sure it is safely secured to prevent it from twisting or thrashing as the rope unspools. Slowly unspool the rope and lay it into flat coils on the floor of your work space. Keep unspooling the wire rope until you are unable to safely remove any more rope from the drum.
3. Brush the wire rope to eliminate exterior corrosion—After the wire rope is on the ground in coils, begin at the end closest to the hoist and start brushing the wire rope vigorously to remove any rust deposits or ingrained debris trapped in between wire strands. Remove as much rust as possible with the brush, but don't use any other tools to scrape at the rust; this will prevent possible damage to the smaller strands.
4. Degrease the wire rope—Once you have removed all signs of rust and other surface debris from the rope, spray it down with an industrial-quality degreasing agent to cut away old lubricants and any stubborn debris that might still be trapped inside the strands. Soak the wire rope well with the degreaser, and allow a few minutes for the degreaser to get between strands.
5. Rinse the wire rope—After the wire rope has soaked in degreasing agent for a short period of time, spray it with a pressure washer to remove the degreaser from the strands. Be sure to move the high-pressure spray around the circumference of the rope in order to penetrate and remove the degreasing agent from all sides.
6. Remove the water from the wire rope—When the wire rope has been rinsed thoroughly, you will need to move quickly to dry up all moisture in the strands to prevent rusting. To dry the rope, apply a strong burst of compressed air along the length of the rope. Be sure to wear eye goggles while blasting the rope with air; this will protect your eyes from possible debris blown out of the strands. Keep applying air until all visible moisture is gone.
7. Lubricate the wire rope—The process of lubricating the wire rope actually involves using two separate lubricants: penetrating and coating lubricants. Each type has its own purpose, as explained below. Here is what you should know about each and how to apply them to the rope:
Penetrating lubricants—Much of the wear and tear placed upon the smaller wire strands of the wire rope occurs on the interior of the rope, as the individual strands slide past each other during the unspooling, spooling, and twisting of the rope. To keep this type of wear minimal, you will need to apply some type of penetrating lubricant to the exterior of the rope and allow it to soak deep into the strands. Penetrating lubricants are lightweight and usually consist of petroleum-based or vegetable-based oils. The simplest way to apply penetrating lubricants is to use a sprayer, but be sure to apply a consistent coat all across the wire rope to ensure it doesn't evaporate before penetrating.
Coating lubricants—For the exterior of wire rope, it is best to use a thicker lubricant that will resist removal from the strands by moisture, usage, or evaporation. These coating lubricants, which often consist of a variety of grease types, are applied by brush, rag, or dipping into the material. Be sure to apply your coating lubricant last to allow the penetrating lubricant to work its way into the core area of the wire rope.
To learn more about taking care of an overhead crane's wire rope or any of its other parts, contact a professional from a company like American Equipment Inc.